Jittery playback in Premiere Pro timeline on one computer (Catalina OS), not on another (Mojave OS)

[jc-miller]

Hi there,

I have recently purchased 2 new iMacs and installed Adobe CC 2020 on them, to match a slightly older iMac I already have. I have confirmed that all 3 computers are running the same version of Adobe Premiere Pro v14.3.0 (Build 38). Additionally, all are installed with Media Encoder v14.3 (Build 39). 

On the newer iMacs, an .mp4 (H.264) provided to me by a colleague, plays jittery in the PP timeline, despite the fact that the playback on QuickTime and VLC is good (not jittery). 

Jittery video example: https://cloudstor.aarnet.edu.au/plus/s/4fOzohIHVe6Cq1D

On the older iMac, there is no issue with jittery playback in the Premiere Pro timeline.

Non-jittery video example: https://cloudstor.aarnet.edu.au/plus/s/yhKNr97kEyH4KiF

When I transcoded the video with the newer machines, I get new .mp4s that are now jittery in QuickTime and VLC, eventhough the original .mp4 played ok in those players. When playing the new mp4 on the older machine, the video is jittery. The older machine does not *create* jittery exports. 

Specs for the new iMacs (jittery playback):

Specs for old iMac (no jittery playback):

Could there be some issue with Catalina? I see that there is a difference between the procesors, but it seems like a trivial difference. Or perhaps there is a codec missing in the newer iMacs that I could install?

Any insight would be appreciated. Thanks,

jc

[jc-miller]

To add to my above post: I have also tried the update for Premiere Pro (v14.4.0 Build 38). This had no effect on the issue.

jc

[jc-miller]

Further things I have tried:

I have re-installed PP2019- this did not fix the issue.

I have tried changing the renderer from GPU Acceleration (Metal)-> GPU Acceleration (OpenCL), and tried the software only option. I have tried this with Media Encoder as well as creating a new project in PP2019 & PP2020. 

I have tried tweaking the Field Options and Modify Clip> Field orders... nothing has worked. I have tried all of this despite the original settings w in PP2020 matched those on my Mojave iMac. 

[@mj]

Hi @jc-miller 

The jitter looks a lot worse than interlaced video playback.

Adobe is recommedning clearing the cache.

Here is a link. https://helpx.adobe.com/premiere-pro/kb/troubleshoot_playback_performance.html#Solution

Some additional suggestions: https://blog.usro.net/how-to-fix-adobe-premiere-cc-choppy-playback/

hth

mj 

[jc-miller]

Hi @mj,

Thanks for your response.

Yah, I knew it was likely not an interlace issue, but I wanted to eliminate *everything*.

I have indeed tried all of those suggestions mentioned on the links you included. Thanks for those. 

I neglected to say this above, but I have only come across this issue with 2 videos thus far, recorded on the same day w the same camera. All other videos I have dealt with behave as expected, even other videos given to me from the same person, and presumably the same camera. I have transcoded thousands of videos on these new machines with no real issues.

I just think it odd that one computer handles these videos, whilst the two newer ones do not. Was hoping it was a quick fix with some settings configuration. Or a known issue w Catalina.  I can move past this by transcoding them on my older iMac, but I do hate unresolved problems.

Thanks!

jc

[@mj]

Hi @jc-miller ,

I  feel you on the unresolved thing.

OK, so you've narrowed it down to two clips.

Let's thinsloce them.

What format, camera, capture settings, etc?

Best

.mj